Optoelectronic waveguide circuits are used extensively in modern optical communication networks. Waveguide circuits are frequently used in the implementation of optical interconnects, optical switches, wavelength division (WDM) multiplexers and demultiplexers. For example, WDM multiplexers are known for their ability to increase the capacity of fiber optic links in a cost effective manner. WDM multiplexers also enable the data rate to be increased by combining several wavelength channels modulated at a relatively slow speed into a single optical fiber.
It is desirable to fabricate optoelectronic devices, such as transceivers, at low cost. An underlying problem with prior art optoelectronic devices is that integrating active components with waveguide circuits creates difficult manufacturing problems. For example, the emitting area of a laser diode needs to be accurately aligned with its waveguide facet in order to achieve good coupling efficiency of the laser source to the waveguide input. However, current manufacturing processes for actively aligning laser diodes with their corresponding waveguide facets are technically difficult, time consuming and costly. For example, placement of the laser diodes with respect to the waveguide facets may need to be accurate to within a few microns, or less. It is also difficult to place laser diodes, such as on a substrate, with such placement accuracies. There is therefore a need for more efficient and precise alignment techniques.
A general object of the present invention is to provide methods for more efficiently and more precisely aligning laser diodes with waveguide circuits.
Another object of the present invention is to write waveguide circuits to produce a circuit in which the waveguide inputs are accurately aligned with the emitting centers of the laser diodes.
A further object of the present invention is to utilize light sensitive polymer materials that can be written with a light beam to create waveguide circuits between the laser diodes and the optical fiber.
Yet another object of the present invention is to provide methods for accurately aligning laser diodes with a waveguide that eliminates need for the prior art active alignment techniques.
A still further object of the present invention is to utilize an active polymer layer that can be written with a light beam to create waveguide circuits between the laser diodes and the optical fiber.